The American Golden Topaz, a 172-faceted topaz weighing 22892.5carat, is the largest cut yellow topaz in the world, and one of the largest faceted gems of any type in the world.[1] Originating from Minas Gerais, Brazil, it was cut by Leon Agee[2] over a period of two years from an 11.8 kg (26 lb avdp) stream-rounded cobble owned by Drs. Marie L. and Edgar F. Borgatta. It was contributed jointly by the Borgatta owners and by Rockhound Hobbyists of America to the Smithsonian Institution in 1988 and is displayed in the National Museum of Natural History in Washington, D.C.